#download{
    float: right;
    padding: 20px 50px 0 0 ;
}
#download a{
    text-decoration: none;
    color: gray;
    font-size: 16px;
}

header{
    text-align: center;
    padding-top: 200px;
    font-size: 25px;
    font-weight: bold;
}

article{
    margin-top:100px;
    position: absolute;
    left: 50%;
}
article a{
    text-decoration: none;
    text-align: center;
    display: block;
    float: left;
    margin: 0 25px 0 25px;
    color: gray;
}